WASHINGTON -- Juanita and Joe Sanders of St. Louis were trying to figure out how to pay for a new roof two years ago when their son came up with a suggestion: a reverse mortgage.

Reverse mortgages allow cash-strapped seniors to draw equity out of their homes to meet financial obligations. The Sanders -- Juanita is 81 and Joe is 97 -- were sold on the idea they could stay in the home they've owned since 1953 and not make any payments.

Their mortgage will be repaid after both have died and the lender either sells the house or their children repay the loan.

"At our age, we didn't want the excess baggage of a monthly payment," Juanita Sanders said. "The equity is there as a line of credit. It stays right there until I need it. It keeps me carefree, not a worry."

The Sanders' reverse mortgage is among 158,000 that the Federal Housing Administration has insured since the program began in 1989. The program has become so popular -- the number of reverse mortgages has more than doubled from 2003 to 2005 -- that Congress earlier this year raised the cap on FHA-insured reverse mortgages, from 150,000 to 250,000.

Two Republican lawmakers from Pennsylvania, Rep. Michael G. Fitzpatrick and Sen. Rick Santorum, have proposed eliminating the cap altogether, an idea that enjoys bipartisan support in Congress. AARP, the influential lobbying group for seniors, and the Department of Housing and Urban Development, which runs the FHA, endorse lifting the cap to meet consumer demands.

FHA-insured mortgages are by far the most popular, accounting for 95 percent of the reverse-mortgage market. Once the last borrower dies, if the value of the home is worth less than the loan and accrued interest owed, the FHA insurance pays the lender the difference.

The legislation's supporters note that lifting the cap on the mortgages would earn the government an additional $8 million in fees in 2007 and $39 million a year after that.

Those fees, about 5 percent of the value of the loan, are one of the disadvantages of reverse mortgages. Another is that interest accrues over the life of the loan, coming due at the end. Heirs have to repay the loan and interest if they want to keep the family home.

Seniors groups generally support proposals to make reverse mortgages available to more elderly homeowners.

But they're also concerned that there is growing sentiment inside and outside Congress for requiring seniors to use money from the mortgages to pay for long-term health-care needs.

As the baby boomer population ages, the mortgages are increasingly seen as a way to relieve states and the federal government of the burden of paying for seniors' in-home care and nursing home care.

The Fitzpatrick-Santorum proposal "seems, at first glance, to be part of a growing movement to force seniors to use home equity in order to pay for their long-term care costs," said Gene Coffey, a staff attorney with the National Senior Citizens Law Center in Washington. "That is not necessarily a good thing."

Advocates for seniors also are concerned about a measure, not yet in effect, that would give seniors a 2 percent discount on their FHA insurance if they use the proceeds from a reverse mortgage to buy a long-term-care insurance policy.

Roy Green, a lobbyist for AARP, notes a potential problem: Insurance policies that expire before policyholders use them would leave those seniors with no equity in their homes and nothing to show for it.